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Don’t you love summer? All the barbecues, outdoor festivals, vacations; school’s out, with all the freedom that goes with that.

I love summer as much as the next guy. Many of my sleep patients don’t, however. I’ve found that there are a couple of times of the year in which my patients experience a spike in their insomnia: during the holidays, and during the summer.

There are several reasons why summertime can trigger or worsen difficulties falling and/or staying asleep. First, many people and many families experience lifestyle changes during the summer as compared to during other times of the year: kids can sleep in in the morning; vacations with jet lag; modifications in work hours or work timing; late-night parties and alcohol use. These changes tend to dysregulate sleep schedules, leading to insomnia. Second, it’s hot! It’s hard to sleep when you’re sweltering and sweating in bed every night; we here in Seattle have been in a month-long heatwave, a major problem because most homes here have no air conditioning! Third, because of the tilt of Earth’s axis during the summer, it’s light out late. As most can easily understand, if the sun is still up in the evening, it feels naturally for YOU to stay up. Exposure of your eyes–and hence your brain–to light has a profound impact on your sleep/wake cycles. No wonder why people tend to have insomnia during these precious summer months!

So here are some pointers to improve your sleep for the remainder of this summer:

1. Choose a time to awaken each morning, and stick with it. Even if you’re not in school or not working, determine a preferred awakening time, set your alarm clock or smart phone for that time, and awaken and get out of bed that same time every morning, including weekends. Your body clock “wants” regularity, no matter what your personal situation. Sleeping in by several hours can throw off your body’s circadian rhythms, dysregulate your sleeping patterns, and promote delayed sleep phase.

3. Keep your sleeping environment QUIET. Whether it’s motorcyclists or firecrackers outside your bedroom window, summertime often means lots of noise outside your bedroom. Insulate your bedroom from the noise the best you can. A fan near the bed can create a white-noise effect to drown out noises from outside. Some may resort to sleeping in another, quieter room in the home, one that is further away from the street for example.

4. Keep your sleeping environment COOL. The fan in the room helps with this, obviously, if you don’t have AC.

5. Avoid naps if you can. Naps are tempting if you have the time and opportunity, particularly if you’re chronically sleep-deprived. However, naps during certain times of the day–particularly the mid- to late afternoon–can cause substantial subsequent problems falling asleep later at night.

6. Don’t spend too much time in bed. Remember, most adults need about 7-8 hours of sleep per night, and your body generally won’t let you sleep more than what your body needs.

School is starting back up before you know it. Enjoy the remainder of your summer!

Here’s a recent story from right here in my home base of Seattle, Washington:

Six days ago, as Alaska Airlines flight #448 took off from SeaTac International Airport, passengers heard someone pounding from below the cabin. A cargo worker was trapped in the cargo compartment of the now airborne Boeing 737. This as-of-yet unidentified man, an employee of contractor Menzies Aviation, called 911 upon realizing he was trapped in the belly of the plane. Upon learning of the presence of someone in the compartment, the pilot turned around for a hasty but safe emergency landing back at SeaTac. No one was injured.

Turns out that this man had fallen asleep in the cargo compartment and he later awakened to find himself–and the plane–airborne and on its way to Los Angeles. The Federal Aviation Administration is investigating the incident, and by report the man is on administrative leave; furthermore, according to an Alaska Airlines spokesperson he has been “permanently banned from ever working again on an Alaska Airlines operation.”

It’s not clear from the news reports why the contractor was asleep in the cargo compartment; by report he passed a drug test subsequent to the event. However, this incident took place around 2:30 in the afternoon on a Monday. From a physician sleep specialist’s perspective, here are some important potential reasons for someone to end up snoozing in the wrong place at the wrong time:

—Irregular sleep schedules, which could be related to a wide variety of causes, from insomnia to some late weekend nights to flip-flopping work shifts (it’s not yet clear if this man’s particular work scheduling involved occasional or recent night-time work).

—Chronic sleep deprivation. Most adults require 7.5-8 hours of sleep per night regularly to feel fully rested during the day, and the most common cause of sleepiness in the U.S. is sleep deprivation.

—Undiagnosed and/or untreated sleep disorders. There are about 100 sleep disorders, ranging from breathing disorders (such as obstructive sleep apnea) to movement disorders (such as periodic limb movement disorder). Commonly associated with excessive daytime sleepiness, these intrinsic sleep disorders often can persist for many years before coming to the attention of a healthcare provider.

I should note here that it’s not necessarily abnormal to feel a little sleepy or “let down” in the mid-afternoon. Our natural tendency to become slightly drowsy or fatigued during that time of day is called the “circadian dip” or “circadian low;” it also provides the reasoning for the “siestas” commonly found in some cultures. However, warningless sleep attacks and irresistible urges to sleep during that time suggest that more than just the circadian low may be at work.

Though I understand that Alaska Airlines does not permit people to “sleep on the job,” my real concern here is why this person experienced a sudden sleep attack or felt compelled to take a nap in the compartment in the first place. I hope that this gentleman has been or will soon be properly evaluated in this regard.

All you parents know what’s right around the corner, if it hasn’t already happened: the start of the new school year!At least for us in the Pacific Northwest, school doesn’t start for another week, so we have one more glorious week of sun and freedom before the beginning of fall classes. But for many of you elsewhere, school has already started in earnest.

One of the many concerns parents have as they transition back into the school year is how their children’s sleep habits will change. Many of us know the drill, from our children’s experiences or our own: all the staying up late on weekends, sleeping in ’til noon on Saturdays and Sundays, the Herculean effort necessary to get out of bed in the morning, especially on Mondays. Though this ritual is very common, particularly for teenagers, the stress and conflict arising from this chronic problem can wreck your family life, not to mention your grades.

This pattern, called delayed sleep phase, arises from the adolescent brain’s natural tendency to cycle its sleep-wake rhythms in a timing scheme that is longer than the 24-hour day. Many of us recall what it was like to be younger and wanting to stay up later and sleep in later if given the chance. The problem with this tendency is that children and teenagers usually engage in activities (i.e., school) that obligate them to entrain their sleep-wake behavior to the 24-hour clock. This conflicts with their biological inclination to go to bed later, resulting in sleep deprivation which makes it more difficult to awaken early in the morning and be awake and alert for classes. Friday night comes ’round, they stay up late, sleep in big-time on weekend days, and then find it impossible to fall asleep early Sunday night because their body clock’s sleep-wake phase has now been delayed from all the sleeping in, so all the sleep debt and sleep deprivation then roll into the new school week, perpetuating the cycle.

There is ongoing controversy about what can and should be done to improve this problem for young people and their families. Though some schools around the country have options of starting classes later in the day, many or most of us parents are obliged to ensure that our children are out of bed and ready for school at times earlier than what they, and their body clocks, “want.”

So what can be done? We can’t change our kids’ brains, though sometimes it’d be great if we could, right? Here are a few tips to help weary parents get their kids sleeping better as we kick off this new school year. As you will see below, these recommendations may be quick to read and absorb, but whether they are easy is another matter. The unfortunate reality is that making these sleep problems substantially better likely will be difficult, at least at first, requiring communication, motivation and insight from the child and patience and support from the parent. Ready? Here goes.

1. Minimize the “sleeping in” on non-school days by setting the alarm clock for reasonably similar times each day to the extent you can. Kids hate this most of all. Sleeping in dysregulates your body clock, causing nocturnal insomnia and daytime fatigue. Sleep schedule dysregulation is why we have jet lag, for example. If your child has to awaken for school at 6 a.m., say, but sleeps in ’til noon on weekends, and then tries to go to sleep early Sunday night, such abrupt changes in the brain would be the equivalent of flying from the west coast to the Bahamas, for example, and back, every week. Regulating the wake-up time may well require a hard sell to the teenager; I’d rather the teen sleep in until 8 a.m. than until noon. This lifestyle modification (and it’s a big one) gets substantially easier if done diligently for a couple weeks, but I won’t lie, it’ll be painful for all involved at first. The child may need some, er, parental assistance in getting up on weekends. A second alarm clock is also an option. Put one alarm clock on the nightstand, and then put the second one further away, set for 2 minutes after the first clock, so that your teen will need to physically get out of bed to turn it off. Make sure the second alarm clock is loud, and the more obnoxious the better.

2. Don’t go to bed until substantially sleepy. If the first step is done properly and done the same way every day, then this second step should fall naturally into place eventually, because the resulting sleep deprivation should make your teen become drowsy gradually earlier in the evening on weekends. Force your child to go to bed too early, however, and residual insomnia results. Taking advantage of children’s sleep needs allows them to fall asleep quickly and earlier (including on Sunday nights) and at the same time get proper amounts of sleep (which for children and teens can be 9-10 hours per night), both of which are important in physical and cognitive development and proper performance in school.

3. Declare a curfew from light and technology. Light exposure greatly impacts our levels of wakefulness and alertness; add to this the perceived need to always be constantly “plugged in” socially through mobile devices, and you have a recipe for “up all night.” Shield your child’s bedroom from outside light and noise, such as with black thick curtains, particularly as these summer months continue to wane. Start dimming your home’s ambient light several hours prior to the projected bedtime. And, finally and importantly, I recommend laying off lit-screen gadgets (including iPads, laptops, and smart phones) 2-3 hours prior to the projected bedtime.

Now that I think about it, I’m pretty sure this last recommendation is actually what kids hate the most. But complete these 3 steps, and utilize them consistently, and chances are your child will sleep better.

The American Academy of Sleep Medicine (AASM) has declared today, March 10, Insomnia Awareness Day this year. The timing of this auspicious occasion is in keeping with the daylight savings time change from over the weekend.

We in sleep medicine circles call today “Black Monday,” the first workday following the one-hour time change each spring. Our body clocks don’t like making changes in their sleep shifts, even if only by a mere hour; anyone who has experienced jet lag knows what I mean. As you know, “springing forward” one hour means having to get up one hour earlier than what our body clocks are accustomed to and thus “prefer.” For those who do not adjust their bedtime schedules accordingly, getting up to get to work, school, or appointments on Black Monday becomes all the more difficult. At the same time, the mild dysregulation of sleep scheduling can also lead to insomnia, particularly if there is already baseline insomnia to begin with.

I’ve covered insomnia in previous posts, and I will go over it and its management in future posts too, because it is such a huge, prevalent clinical problem and growing public health concern. For the purposes of today’s Insomnia Awareness Day post, however, I will concentrate simply on what insomnia means.

The definition of insomnia, as accepted by the AASM, is the “subjective perception of difficulty with sleep initiation, duration, consolidation, or quality that occurs despite adequate opportunity for sleep, and that results in some form of daytime impairment.” [Schutte-Rodin S; Broch L; Buysse D; Dorsey C; Sateia M. Clinical guideline for the evaluation and management of chronic insomnia in adults. J Clin Sleep Med 2008;4(5):487-504].

As such, insomnia is by its very nature subjective, meaning that you can have insomnia no matter how much actual sleep you really get, and implying that the time spent awake in bed is bothersome. Among the many impairments associated with insomnia are a feeling of unrefreshing sleep, low energy levels during the day, daytime sleepiness, emotional problems (like depression and anxiety), morning headaches, difficulties with memory and concentration, reduced work productivity, and a propensity toward industrial and motor vehicle accidents.

This definition is important. You can have insomnia even if you get a full 8 hours of sleep each night (such as if you are spending 12 hours trying to sleep each night). Conversely, 4 hours spent in bed spent awake each night casually watching television but not trying to sleep do not constitute insomnia. Note also that the definition does not address potential causes, of which there are hundreds–causes can range from a can of Mountain Dew at 10 p.m. to one’s mental perception of dread and frustration associated with previous difficulties falling asleep. The definition of insomnia also helps provide a rough roadmap to therapy. My own practice philosophy for patients with chronic insomnia (i.e., insomnia that lasts for a month or longer) is to identify the underlying causes and to improve the insomnia by improving or resolving the problems causing it.

From a clinical perspective, chronic insomnia management can range from relatively straight-forward to extremely challenging. Doctors that identify themselves as “physician sleep specialists” should have the expertise and willingness to handle cases of insomnia, including the tough ones. Enlist their help should your insomnia become sufficiently problematic. Help IS available.

Our old, well-worn first-gen iPad has gotten a LOT of use over the years, and admittedly much of the use has been in bed at night. I read quite a bit, and though I still prefer good old-fashioned paper print books (I’m always in the middle of 2 or 3), our iPad has also become a regular staple in my routine prior to turning off the lights for the night, primarily for e-mails and this blogsite adventure I started several months ago. My wife and I have never had problems falling asleep as a result of iPad use, but many of my patients have found their insomnia improves with modifications in their habit of using electronic devices involving bright backlit screens in bed.

We’ve all experienced activities that cause us to end up going to sleep later than what we intended. However, backlit electronic pads can contribute to difficulties falling asleep if used shortly prior to bedtime, and there are a couple reasons why. First, the content of what you’re doing or reading can obviously play a role. Whether it’s an exciting video or the discovery of the latest shoe sale on Zappos, anything that you’re exposed to that is visually or emotionally stimulating or is of emotional importance to you can create an alerting effect that delays the onset of drowsiness. Second, and importantly, the light exposure from the backlit screen (particularly when full-color) can also have a stimulating effect.

Light tends to inhibit the release of melatonin in your brain. There is a thin band of neurologic tissue–called the retinohypothalamic tract–that connects your eyeballs to the hypothalamus, the seat of your body block. This tract is stimulated when the back of your eye–the retina (the cells of which are illustrated above)–are exposed to bright light, and the resulting signal to the brain leads to a sensation of wakefulness and alertness, the exact opposite of what you want when your goal is to fall asleep for the night. This is why it’s important to avoid bright light late at night and to expose yourself to bright light early in the morning if you have insomnia.

The problem is that modern backlit e-readers are not only capable of emitting very bright multi-colored light, but also held very close to your eyes: unlike your television set, which is across the room, your iPad is on your lap or held right in front of your face, bathing your retinas with light.

So here are some suggestions for you if you’re having difficulties falling asleep following backlit e-reader use at bedtime:

1. Turn down the intensity or brightness of the screen.2. Try an e-reader without a backlit display, such as a basic Kindle.3. Call me old-fashioned, but you could always go back to paper books, and save your e-mail for tomorrow morning.4. Read in relatively dim light.5. In general, avoid intense light for about 1-2 hours prior to your projected bedtime.

The other day I was asked about daytime naps: “is it better to take a nap when you are feeling really tired that day or try to go to bed earlier instead and skip the nap?” In order to best answer the question, it’s important to know what is causing you to want or need the nap in the first place.

The science of sleep regulation is quite complex. Sleep intensity is mediated by what is called the homeostatic mechanism of sleep, the specifics of which are beyond the scope of this blog entry. Simply stated, the principles of sleep homeostasis dictate that sleep deprivation results in a compensating increase in intensity and duration of sleep, and excessive sleep (such as related to a daytime nap) reduces the inclination for sleep. Taking a nap during the day implies daytime sleepiness, so let’s explore why one may be sleepy during the day.

One of the most common causes of daytime sleepiness is simple sleep deprivation. If you’re getting 5 hours of sleep per night, for example, when your body needs 8, then likely you will not need to take a nap during the day any longer if you then gradually increase your sleep time to 8 hours per night, because by satisfying your body’s natural sleep needs consistently you should eventually feel substantially more awake and alert throughout the day.

Another common cause of daytime sleepiness is insomnia. If you get less sleep at night because you’re awake a lot in bed, an obvious consequence would be feeling fatigued and drowsy during the day. The problem is that taking a nap during the day can cause or worsen insomnia, particularly if the nap is prolonged and/or taken in the mid-afternoon to early evening; you tend to get a “second wind” and feel more awake and alert later than what you desire, resulting in further sleeplessness at night.

Finally, you could be sleepy during the day due to a problem with the quality (as opposed to the quantity) of your sleep. Numerous sleep disorders can cause substantial drowsiness during the day even if you get your 8 hours per night: obstructive sleep apnea, upper airway resistance syndrome, periodic limb movement disorder, and narcolepsy to name a few. A good general rule to follow: if you regularly get 7-8 hours of sleep per night and you’re consistently struggling to stay awake during the day when 7-8 hours per night used to satisfy your sleep need in the past, and if the sleepiness can’t be explained by some other factor (like medications or alcohol), you may want to see a specialist like me.

1. If you nap because you’re sleep deprived, there is often residual sleepiness between the time you awaken in the morning and the time your nap starts.

2. If you nap due to insomnia, a vicious cycle can develop: the nap can cause or worsen the insomnia, which then reduces your nocturnal total sleep time, which then makes you feel more sleepy during the day, which then makes you want to nap more. In extreme cases people’s bedtime schedules can be completely turned around due to this problem, such that they become essentially nocturnal, sleeping throughout much of the day and remaining awake all night.

3. Taking a nap to sustain you for the rest of day may “mask” concerns for an occult sleep disorder.

Bottom line here: if the nap doesn’t cause difficulties falling or staying asleep at night, and if you don’t have substantial daytime fatigue or sleepiness prior to the nap, and if you’re confident you know the reason why you need the nap in the first place (such as staying up too late the night before), then I think there’s probably not much of a problem with taking that nap. However, if you find yourself unable to stay awake during much of the day, if you are substantially sleepy during the day despite getting proper amounts of sleep, or if you are having mounting insomnia in this setting, there should be further concern about what is happening.

I’ll add several additional points before Sleep Help Desk closes for today. First, naps can be intentional (i.e., laying down with the intention of taking a nap) or unintentional (such as falling asleep by accident in front of the television). Second, if you doze off on the couch at 10 p.m. before you go to bed, that’s still a nap! That late-night nap can cause difficulties falling back to sleep once you do go to bed, so try to avoid dozing off in the evening until you’re in bed intending to sleep. Finally, to answer the original question posed to me above, I suggest not going to bed too early if you choose to not take the nap. If you go to bed way earlier than usual, you can still have insomnia even if you’re sleep deprived, because your body clock “wants” regularity nonetheless. The idea is to gradually increase your total sleep time such that you reliably get proper amounts of sleep every night.

Trivia question: who is the famous person napping in the photograph above? Write me with your answer!

I’ve been asked recently by a friend why she finds herself awakening at 2 a.m. virtually every morning.

Many people have experienced this phenomenon, a tendency to awaken at least briefly around the same time every night. There may be many potential reasons for this, ranging from your pet to a need to urinate or a spouse coming to bed for sleep later than you. The expression of certain hormones in your brain throughout the night might play a role. However, for many people, these brief awakenings may also be related to your brain’s natural rhythms for sleep.

To describe human sleep physiology as simply as I can, human sleep is very dynamic. We sleep in cycles, called ultradian cycles, in which lighter stages of non-REM (called stage N1 and N2) sleep are followed by deeper forms of non-REM (formerly called stage 3 and stage 4 sleep, but now called stage N3, or slow wave) sleep and then, to varying degrees, rapid eye movement (REM, stage R, or dream) sleep. In general, the amount of deep non-REM sleep we have per cycle is highest during the first one-third of the night’s sleep, and the amount of REM sleep we have per cycle gradually increases as the night progresses (which explains why we tend to remember our dreams most around, say, 4-6 a.m.). Exactly how and why we have been designed neurologically to sleep in this way are a mystery. A typical human adult’s ultradian cycle lasts for about 90-110 minutes. Generally it’s most difficult to awaken fully from N3 sleep, and it’s quite easy to awaken fully from REM sleep. This explains why you often feel very groggy if you’re awakened abruptly during the first 2-3 hours of sleep, but may find yourself awakening easily and quickly from a dream later at night.

The primary point I want to make with all this is that between these ultradian cycles, there are normally and naturally periods of arousal from sleep. There can be several of these brief arousals in a typical night. In children, adolescents, and young adults, these arousals are generally very brief, perhaps lasting for only several seconds; these awakenings are not usually enough to remember, in part because younger people tend to have a lot of slow wave sleep), leaving you with the feeling that you are sleeping uninterrupted all night long, even though you have likely in reality aroused several times. Once you reach middle age, however, such as your 40’s and 50’s, the tendency to recall these arousals from sleep can gradually increase, and the duration of the typical arousal from sleep may gradually increase as well. This may explain why some people remember awakening, say, at 3:30 a.m. on the dot every night. Finally, when you become elderly, in your 70’s and 80’s, say, still more frequent awakenings may occur due to the naturally increased sleep disruption that occurs as your brain becomes more brittle with age.

Why is this all important? Because some people freak out over a spontaneous recalled arousal from sleep in the middle of the night, and this substantial concern or annoyance can generate enough worry or frustration to actually cause persistent wakefulness subsequent to that arousal, potentially triggering chronic insomnia.

Take-home point here: if there is a brief awakening around the same time most nights, and there is no specific symptom or problem that causes the awakening, and if there aren’t substantial problems falling back to sleep, and if there is minimal sleepiness during the day, my sense is that the awakening is probably not much to worry about. If there are substantial problems associated with the awakenings, however, it may be worthwhile to bring that to a doctor’s attention.